Photographer's notes: "With the bridge complete and open, the bridge, dam and lake now share the Black Canyon." Site Name: Mike O'Callaghan-Pat Tillman Memorial Bridge

Photographer's notes: "With the bridge complete and open, the bridge, dam and lake now share the Black Canyon. January 14, 2011. Note: This is the uncropped version of this photograph. I chose to crop out the horizon for use in the book and exhibition." Site Name: Mike O'Callaghan-Pat Tillman Memorial Bridge

Photographer's notes: "Aerial view of the dam and completed bridge arch before construction of the piers (columns) began. From the air, the arch appeared delicate and fragile. September 10, 2009." Site Name: Mike O'Callaghan-Pat Tillman Memorial Bridge

Photographer's notes: "Ironworkers in Manbaskets, April 29, 2009 - Ironworkers were transported in manbaskets via a high line crane system to the end of the Arizona arch segment." Site Name: Mike O'Callaghan-Pat Tillman Memorial Bridge

Photographer's notes: "Aerial view looking downstream of the bridge arch construction, the Nevada side hairpin turn of the old road, and the Colorado River, June 30, 2009." Site Name: Mike O'Callaghan-Pat Tillman Memorial Bridge

Photographer's notes: "Aerial view of bridge and the hairpin turn of the old Nevada road, June 30, 2009." Site Name: Mike O'Callaghan-Pat Tillman Memorial Bridge

Photographer's notes: "From the air, the relationship of the Colorado River, bridge, dam and Lake Mead come into perspective." Site Name: Mike O'Callaghan-Pat Tillman Memorial Bridge